Vacuum breaker



Nov. 17, 1942. w. E. sLbAN ET m.

VACUUM BREAKER Filed July 30, 1941 i g 9% i I Fig. 4

M .mwc mSw F N MW .A A 5 uw 0 Y B ATTORNEYS Patented Nov. 17, 1942 2,302,151 I VACUUM BREAKER William E. Sloan, River Forest, and Irving H.

Russell, Oak Park, Ill., assignors to Sloan Valve Company, Chicago, 111., a corporation of II- linois Application July so, 1941, Serial No.'4Q4,6 i6

14 Claims.

This invention relates to an improved vacuum breaker which is adapted to be installed in a water supply pipe line extending for example from a flush valve to a water closet bowl or other fixture. I

Vacuum breakers are customarily provided in water supply systems where the feed line furnishes water for sanitary purposes, as well as for other uses such as drinking, washing or cooking. These vacuum breakers are a necessary precaution since the sanitary fixtures, including water closet bowls and bathtubs, are connected to the water supply pipe line where there is grave danger that the water supply pipe line may become contaminated by siphonage of the liquid from the Waste fixture into the water supply pipe line when a vacuum or sub-atmospheric condition occurs in the water supply pipe line, thus contaminating the water used for drinking and cooking purposes.

It is an object of the invention to provide an improved vacuum breaker for preventing this siphonage, which is provided with an air inlet and which is comparatively simple in construc-' tion and inexpensive to manufacture, and is efiicient and durable in use, and pompactly arranged so as to be inconspicuous when installed in position.

The invention has as a further object to provide a vacuum breaker where the valve for the water port is provided with means for holding the valve close to the water port seat when the device is not in operation, the valve, being provided' with means which project beyond the face thereof toward the water port seat for opposing the means for holding the valve close to the water port seat, when water from the flush valve is passing therethrough, and for assisting the means tending to move the valve away from the air inlet port seat when a sub-atmospheric condition exists to cause a backward flow of liquid against said valve, the one element therefore having two opposite functions.

The invention has a further object to provide a vacuum breaker with a water discharge port and an air inlet port with a pivoted valve intermed ate them, with means for causing the valve to close the air inlet port when water is passing through the vacuum breaker and to maintai it closed until the flow of, water has substantially ceased, thereby preventing air from being drawn through the air inlet port to create objectionable noise while water from the flush valve is passing through, the vacuum breaker.

The invention has as a further object to provide a vacuum breaker having a water discharge port and an air inlet port with a valve pivotally suspended intermediate them, the valve having a part projecting from the face thereof toward the water port, a portion of said projecting part at the bottom of the valve, being flexible so that during the maximum flow of water it bends toward'a position parallel to the valve, giving a full flow of water through the vacuum breaker and returns to its projecting position as the flow of the water decreases, to increase the effect of the water in maintaining the valve in its air'inlet port closing position.

The invention has as a further object to provide a vacuum breaker having a water discharge port and an air inlet port and a valve pivotally suspended intermediate them and normally in a position to maintain them both open, said valve having a weight attached to its face opposite the air inlet port and means projecting from the side thereof opposite the water discharge port,.which is acted upon by the water to assist in opposing the action of said weight and which ceases to oppose the action of said weight when the water from the flush valve ceases to flow through the vacuum breaker.

The invention has as a further object to provide a vacuum breaker wherein the assembly of the parts is simplified and having a cheap and eflicient means for connecting the vacuum breaker in the water connection where it is employed, and the provision of a valve structure which eliminates various soldering operations, which will /prevent the escape of water to the outside. I Other, objects and advantages are more fully pointed out in the following description:

This invention is in the nature of an improvement upon a co-pending application of William E. Sloan and Irving H. Russell, filed October 13,

1939, Serial No. 299,336.

Referring now to the drawing which illustrates a preferred embodiment of the invention;

Fig. l is a front view of a water closet installation including a flush valve equipped with a vacuum breaker embodying the invention;

Fig. 2 is a cross-sectional side view of the vacuum breaker shown in Fig. 1;

Fig. 3 is a cross-sectional side view of a portion of the-device taken on line 3-3 of Fig. 2;

Fig. 4 is a view similar to Fig. 2, showing the parts during one phase of the operation of the vacuum breaker;

Fig. 5 is a perspective view of the partition wall and valve member support; ,7

Fig. 6 is a perspective view of the metal insert of the valve member.

In the drawing, Fig. 1 is a view showing a vacuum breaker embodying the invention in connection with an ordinary water closet. As here illustrated, a flush valve or metering valve 4 of wellknown construction is provided with the usual adjustable throttle or stop valve 5 in the connection which supplies water to the fiush valve. The flush valve 4 is provided with the usual handle 6, which upon being operated, causes a metered flushing operation of the flush valve. The outlet of the flush valve 4 is associated with a discharge pipe 1 which discharges water into a water closet bowl 8. Arranged in position between the outlet end of the flush valve 4 and the inlet of the discharge pipe 1 and well above the spill line of the water closet bowl 8, is a vacuum breaker indicated generally at 9, embodying one form of the invention.

In its preferred construction, the vacuum breaker 9 comprises a tubular member or casing l0, providing an upper inlet opening and a lower outlet opening. The casing is supported by an upper threaded annular inlet fitting I I and a lower threaded annular outlet fitting I2, preferably provided with an inner tapered reentrant portion I3, into which the lower end of the tubular member I is forced in order to provide a fluid tight press fit connection. The outlet fitting I2 is also provided with a ledge or stop I4 to provide an abutting surface to limit the inward movement of the tubular member I9 into the outlet fitting. A slip joint connection is provided for connecting the outlet fitting l2 with the discharge pipe 1 and consists of coupling nut I5 having a threaded engagement with the outlet fitting I2 and which tightly compresses a suitable rubber packing I6 against the lower edge of the outlet fitting l2, to tightly seal and hold the discharge pipe I onto the outlet fitting I2. A friction rzng I! is preferably arranged between the coupling nut I5 and the packing I6 to prevent curling of the packing when the nut is tightened. The stop I4 limits the distance that the discharge pipe I can be inserted into the outlet fitting I2.

At its upper end, the tubular casing member ID projects into the upper inlet fitting I I, and an inner shoulder I8 projecting from the upper fitting II contacts the outer cylindrical wall of the member I0. Suitable sealing means I9 is arranged on top of the shoulder l8, and when the outlet fitting I I is screwed into threaded engage ment with the outlet of the flush valve 4, the packing I9 is compressed against the outer walls of the tubular casing II] to eifect water-tight sealing engagement therewith. By this means a simple, reliable and readily assembled arrangement is provided for connecting the vacuum breaker 9 in position between the discharge pipe 1 and the flush valve 4.

An outer protective shell or casing is axially disposed to enclose the inner tubular casing I0, and is secured in position to the lower portion of inlet fitting II and below the ledge I8 by soldering as indicated at 2|. At its lower end the shell 20 is also secured as by soldering at 22, to the upper end of the outlet fitting I2. Adjacent to its upper end, the outer shell 29 is provided with one or more openings 23 and 24, which connect the inside of the vacuum breaker with the outer atmosphere. A hood-like portion 25 on the upper fitting II protects and screens the openings 23 and 24 in the shell 20 from entry of dirt, dust, insects, etc., which may interfere with the proper operation of the device. There is a space 26 between these two members I0 and 29 for the purpose of catching any splashing of Water which may be caused by operation of the device.

The tubular casing I0 is provided with an air inlet preferably produced by piercing its wall, the

material thereof being formed and bent inward to provide an air inlet 21, the inner edge of which is suitably machined to provide an air-inlet seat 28, preferably formed at a slight angle and which diverges outwardly and downwardly from the vertical position of the vacuum breaker 9 itself.

The central waterway portion of the vacuum breaker 9 is separated into a supply chamber and a discharge chamber by means of a central partition 29, which is angularly and diagonally disposed within the tubular casing II], which is preferably made of a single piece of sheet metal bent and formed into the general shape illustrated in Fig. 5, and is provided at its lower end with a transverse portion 39 arranged at substantially right angles to the main body of the partition 29. At the upper end a similar transverse portion 3| is provided, which projects outwardly in the opposite direction from the partition 29. The transverse portions 30 and 3| extend to opposite side walls of the tubular member I0. The transverse lower portion 30 is provided with a lug 32 integral therewith. which extends through an opening in the associated wall of the tubular member I0, and is soldered thereto to prevent liquid leakage at this point. The transverse partition 3| is provided with a similar lug 32' which extends through the side wall of tubular member I0, and is soldered thereto. The partition 29, as well as the transverse portions 30 and 3|, make intimate contact at all points with the wall of the vertical tubular member I0 in a substantially fluid-tight manner. With this arrangement of the partition 29 within the vacuum-breaker device, the need for extensive soldering operations or other means for tightly sealing and supporting the partition is eliminated, thereby eifecting a considerable saving in the cost and assembly of the device.

The lower transverse portion. 30 of the partition 29 is formed and arranged so as to extend downwardly in the direction of the water flow through the device. Likewise, the sides and other surfaces of the partition 29, as well as the other portions of the transverse portions 30 and 3 I, are so rounded and merged together as to present the least possible amount of resistance to the free passage of the liquid supply through the device.

The diagonal partition 29 at substantially its mid-portion is provided with an annular discharge port, having a check-valve seat 33 angularly disposed with respect to the vertical position of the vacuum breaker, and which diverges outwardly and downwardly therefrom. It is disposed in a position substantially opposite the airinlet seat 28, and somewhat spaced apart therefrom.

A novel valve member is provided for effecting a closure of the passage through either the check-valve seat or the air-inlet seat, comprising a disc-shaped valve member 34 adapted to be pivotally swung into selective engagement with either of the seats, and normally suspended in an intermediate position between and normally out of contact with both of said seats. The valve member 34 comprises a thin metal disc 35,

imbedded or molded within a flexible covering 36, preferably of rubber, provided with a flexible annular lip portion extending substantially'around the periphery of the valve member 34. This rubber lip portion projects outwardly in a direction so that when the valve member 34 is in seating engagement with the check-valve seat 33, the lip portion is in overlapping relation with this seat, and also provides a means whereby the flow of liquid through the vacuum breaker is efiective at the lower rates of flow to hold the valve member 34 in seating engagement with the air-inlet seat 28.

The valve member 34 is preferably biased against gravity pull in a normal inactive position, closer to the check-valve seat 33 than to the airinlet seat 28, so as to normally provide a relatively large opening to the atmosphere from the interior of the vacuum breaker. biasing means may be used. As herein shown, it comprises a metal weight 3'! supported upon the back of the valve member 34 and securely fastened to the metal insert 35 of the valve. The valve member 34 is of the pendant or pendulum type and normally hangs freely between the two seats due to the action of gravity, so it will not stick or freeze to one of the seats between periods of its operation. It is suspended in a position from the lower side of the upper transverse portion 3| of the partition 29 in a manner which facilitates the assembly thereof. The upper end of the metal valve insert 35 is provided with a curled-over portion (see Fig. 6) which embraces a pivot pin 38 from which the valve member 34 is freely suspended. Pivot pin 33 is supported at either end by means of slots 39 cut in leg portions 40 of the supporting bracket 4|, as shown in Fig. 5. In assembling the valve member 35 in its supported position, the leg portions 40 of bracket 4| are slipped through slotted openings 42, spaced apart in the upper transverse partition portion 3! after which the pivot pin 38 is inserted into the slots 39. The bracket 4| thereby rests on top of the transverse portion 3| with the legs 4|! depending therefrom in the position shown in Fig. 3. A lug 44, preferably Any suitable struck up from the transverse portion 3!, is bent downward on top of the bracket 4| and thereby securely holds the bracket and valve member 3 4 in its pivoted position. In order to provide for reliable seating of the valve member 34 upon either the check-valve seat 33 or the air-inlet seat 28 when there are variations or too great tolerances in the machining and positioning of the seats, the pivot pin 38 is arranged to autor. matically move sideways an appreciable distance in the slotted supporting openings 39 so that the valve member 34 can compensate for the unequal or uneven seating surfaces when it is moved into engagement therewith. This loosely supported pivot arrangement for the valve member likewise prevents binding or sticking of the same and insures free unrestricted swinging movement during all stages of its operation.

Valve member 34 is likewise arranged with the lower portion of its lip indicated at 48, having a greater degree of flexibility than the remaining portion of the valve. To provide for this, the metal insert disc 35 is arranged with stiffening portions 45 and 46, which are imbedded in opposite side portions of the rubber disc constituting the valve member 34, the stiffening portion being omitted or cut away at 4'! on the lower downstream side of the valve member. With this arrangement, the lower flexible lip portion 48 is located on the lower peripheral edge of the valve member in the direct path of the flow of liquid water supply line close quickly and have a large opening for the admission of the air for breaking the vacuum. The present device meets these conditions. It will be noted that the valve 34, when the flush valve is not operating, is maintained in a position close to the seat of the water discharge port, thus enlarging the air opening and allowing a large amount of air to instantly enter when'there is a vacuum condition present. The lip portion of the rubber covering 36, when the flush valve is not operating, surrounds the periphery of the water discharge port. If there is any back flow of liquid from the bowl, this lip tends to prevent this liquid from flowing back through the port. Furthermore, when the liquid strikes the lower part 48 of the lip, the pressure of the liquid on this part 48 applies a closing pressure on the valve 34 before the liquid rises very high and closes the valve at an earlier stage than it would be closed if the closure depended entirely upon the pressure of the liquid on theback of the valve.

While we have described a particular construction of vacuum breaker, it is of course evident that the parts may be varied in many particulars without departing from the spirit of the invention as embodied in the claims hereto appended, and we therefore do not limit the invention to the particular construction shown.

The use and operation of our invention is as follows:

In the normal position when no water is flowing through the device, the valve member 34 is suspended freely under control of gravity in a position between the check-valve seat and the air-inlet seat and out of engagement with either one. Assume now that a flushing operation of the toilet bowl 8 takes place. The inlet liquid supply passes through the flush valve 4, discharging through the outlet thereof into the supply chamber of the vacuum breaker 9. The flow of water in passing through the tubular casing I0 is slightly diverted from its direct downward fiow by the diagonal position of the partition 29 and the transverse portion 30. The flow is directed in a path substantially as illustrated in Fig. 4, impinging directly against the left-hand side of the valve member 34, whereupon the valve member 34 is immediately swung over about its pivot 38 in a right-hand direction into engagement with the air-inlet seat 28. Thus the splashing of water through the air passage 21 is quickly prevented, and the valve member held in engagement with the air-vent seat due to the full force of the water being deflected against it. This action is accelerated and effectively maintained by the provision of the lip portion of the flexible cover 36 on the valve member. With the valve member held in the position pointed out, a substantially large waterway opening or port is provided through the check-valve seat 33, and the shape of the partition 29 is such as not to seriously restrict or impede the free flow of water through the vacuum breaker.

The energy supplied by the high rate of water flow through the vacuum breaker is also effective to bend over and straighten out or distort the lower lip portion 48 of the valve member 34, so that this lip portion extends substantially downstreamward and substantially parallel to the flow of water, as illustrated in Fig. 4, thus providing a somewhat larger and freer waterway and insuring a greater volume and rate of flow than would ordinarily be provided without such provision.

As is well known in the operation of a flush valve in supplying the desired metered quantity of water to a toilet bowl 8, there is a period in its operation shortly before the liquid supply flow is terminated, which is termed the refill. This refill is required in order to furnish the seal for the trapway in the closet bowl. When the shutoff operations of the liquid supply take place, the rate of fiow through the vacuum breaker gradually diminishes. This low rate of flow in passing through the vacuum breaker is insufficient to force the lower lip portion 48 of the valve member 34 into its downstreamward straight condition, and as a result the lip portion assumes its overlapping transverse position as shown in Fig. 2. In this position, the lip portion is in the path of the low or greatly reduced water flow, where it can be acted upon thereby and continue to maintain the valve member 34 in closed engagement with the air-inlet seat 28. Ordinarily in the devices heretofore used the column of water which is rapidly flowing through the discharge pipe I, immediately prior to the complete shut-off thereof, creates a sub-atmospheric condition within the discharge portion of the vacuum breaker, which condition produces a suction action tending to dislodge the valve 'member 34 from its sealing engagement with the airinlet seat 21, and produce an objectionable noise. The present device, wherein the air inlet is maintained closed at the reduced rate of flow of the water, eliminates this objectionable feature.

After the free flow of water through the vacuum breaker 9 has ceased completely, the weight 31 carried by the valve member 34 is sufiiciently heavy to cause the valve member to swing out of engagement with the air-inlet seat 28 into its normal position intermediate the airinlet seat and the check-valve seat and so it will not inadvertently stick to the air-vent seat as a result of being immersed in the liquid supply due to the adhesive qualities of the water.

If, after the water from the flush valve has ceased flowing down through the pipe, a subatmospheric condition develops within the device, the valve member 34 is caused to be immediately moved into engagement with the check-valve seat 33, thereby preventing the back flow of the contaminated liquid into the supply pipe line. The large air inlet, which under these conditions connects the interior of the vacuum breaker with the outside atmosphere, serves to effectively break the vacuum formation. The extending lip portion 36 of the valve member 34 which now hangs in overlapping relationship to the checkvalve seat 33 serves to more closely hold the valve on its seat, and also renders the valve member more sensitive to the back flow action and greatly assists the same in swinging into closing engagement with the check-valve seat. The member 36, and particularly the lip 48 thereof, has two opposite functions: It opposes the means, that is the weight 31, for holding the valve close to the water port seat when the water from the flush valve is passing therethrough, as the water strikes the lip and tends to force the valve 35 to a more fully open position. It assists this means, or weight 31, in tending to move the valve away from the air-inlet port seat when a subatmospheric condition exists because of backward flow of liquid against the valve, as this backward flow of liquid strikes the lower portion of the lip 48 before it strikes the face of the valve 35 and tends to move the valve to close the water inlet port.

While we have shown the vacuum breaker as being used in a water closet combination, it is of course understood that it is applicable for use in installations of any other nature where the danger of contamination of the pure-supply water is present.

We claim:

1. A vacuum breaker for a liquid supply stream comprising a tubular casing having a water dis-- charge port and a surrounding seat therefor, and an air inlet port and a surrounding seat therefor, said seats positioned opposite each other and spaced apart, a valve member arranged within said tubular casing intermediate and normally out of engagement with both of said seats and movable into engagement with either of said seats to close either of said ports, means connected with said valve member tending to move it away from said air inlet port seat and closer to said water discharge port seat, and a projecting lip connected with said valve member which projects therefrom towards said water discharge port seat, the lower portion of said lip projecting beyond the face of the seat for said water discharge port when no water is flowing through the device.

2. A vacuum breaker for a liquid supply stream comprising a tubular casing having a water discharge port and a surrounding seat therefor, and an air inlet port and a surrounding seat therefor, said seats positioned opposite each other and spaced apart, a valve member within said tubular casing intermediate said seats and movable into engagement with either of said seats to close either of said ports, means connected with said valve member tending to move it away from said air inlet port seat, and a projecting lip connected with said valve member which projects therefrom towards said water discharge port seat, the lower portion of said lip projecting beyond the face of the seat for said water discharge port when no water is flowing through the device, the lower portion of said lip being flexible so that during the maximum flow of water through the device, it bends toward a position parallel to the main body of the valve member, providing a full flow of water through the vacuum breaker.

3. A vacuum breaker for a liquid supply stream comprising a tubular casing having a water discharge port and a surrounding seat therefor, and an air inlet port and a surrounding seat therefor, said seats positioned opposits each other and spaced apart, a valve member within said tubular casing intermediate said seats and movable into engagement with either of said seats to close either of said ports, means connected with said valve member tending to move it away from said air inlet port seat, and a projecting lip connected with said valve member which projects therefrom towards said water discharge port seat, said projecting lip having rigid side portions and a flexible lower portion defining the periphery of said valve member together with flexible annular inner portions on opposite sides of said valve member for closure upon the associated seats, the lower portion of said lip projecting beyond the face of the seat for said water discharge port when no water is flowing through the device, the lower flexible portion of said lip being arranged so that during the-maximum flow of water through the device, it bends toward a position parallel to the main body of the valve member, providing a full flow of water through the vacuum beraker, and returns to its projected position as the flow 'of the water decreases to increase the effect of the water upon said projecting lip in maintaining the valve member in its air inlet port closing position.

4. A vacuum breaker for a liquid supply system comprising a tubular casing having a water discharge port with a seat therearound and an air inlet port with a seat therearound, a valve member arranged within said tubular casing for movement into engagement with either of said seats selectively, biasing means normally acting to position said valve member out of engagement with both of said seats when no liquid is flowing through said casing, and means on said valve member acted upon by a low rate of flow of the liquid supply to hold the valve member in engagement with the air inlet seat against the biasing action of said biasing means.

5. A vacuum breaker for a liquid supply system comprising a tubular casing having a water discharge port with a seat therearound and an air inlet port with a seat therearound, a valve member arranged in said tubular casing for movement into engagement with either of said seats, a weight on said valve member effective to position said valve member normally away from each of said seats but closer to one of said seats, and a projecting portion on said valve member arranged in the path of the liquid supply flow to hold the valve member in engagement with one of said seats at a low rate of flow in opposition to the efiect of said weight.

6. A disc-shaped valve member arranged for pivotal movement into engagement with two separate valve seats selectively, a flexible lip portion of flexible material formed on said valve member overlapping one of said-seats when said valve member is in engagement therewith, and stiffening means for a part of said lip portion, said lip portion having a section thereof free of the stiflening means so as to be more flexible than the remaining portion of said lip.

7. A vacuum breaker for a liquid supply system comprising a tubular casing having a water discharge port with a seat therearound and an air inlet port with a seat therearound, a discshaped valve member in said tubular casing arranged for pivotal movement into engagement with either of said seats selectively, a flexible lip portion formed on the periphery of said valve member overlapping the seat for the water discharge port when said valve member I8 is in engagement therewith, and stiffening means for said annular lip portion having a portion on the downsteam side of said valve member omitted to enable the flexible lip portion to be straightened out at that point by the action of the liquid supply flow so as to reduce the resistance to the liquid supply flow through said casing.

8. A vacuum breaker for a liquid supply system comprising a tubular member having a water discharge port with a seat therearound and an air inlet port with a seat therearound, a discshaped valve member in said tubular member arranged for movement into engagement with either of said seats selectively, and a flexible lip portion arranged on said valve member, said flexible lip portion having a part thereof overlapping said water discharge port seat when thevalve member is in engagement therewith and being acted upon by the liquid supply flow to hold the valve member in engagement with said air inlet port seat, a portion of said flexible lip portion being straightened out on the downstream side of said valve member at high rates of flow of the liquid supply so as to reduce the resistance to the free flow thereof, while at low rates of flow the lip portion remains in its initial position and the low rate of flow is effective to continue to hold the valve member in engage-V ment with the air inlet port seat to prevent noise as the liquid from the liquid supply through the vacuum breaker is decreasing.

9. A vacuum breaker for a liquid supply system, comprising a vertically disposed tubular casing, an air inlet port formed in the side wall of said tubular casing, a valve, seat therefor, a partition wall having a portion arranged diagonally within said tubular casing and with upper and lower disposed portions, a water discharge port formed in the diagonal portion of said partition wall, a valve member -pivotally supported from the upper one of said partition portions and adapted to swing into engagement with either the water discharge port seat or the air inlet port seat, said partition wall being in close intimate contact at its periphery with the walls of said tubular casing, and pro ecting lugs formed on the upper and lower partition portions piercing the wall of said tubular casing for supporting said partition therein.

10. A vacuum breaker for a liquid supply system, comprising a vertically disposed tubular casing, a partition wall disposed within said tubular casing extending in the path of the liquid supply flow, said partition wall being so shaped and formed as to reduce the resistance to the free flow of the liquid supply and defining a diagonal section together with an upper and lower transverse section, the edges of said sections being in abutting engagement with the inner face of the tubular casing, the junction points of said upper and lower transverse sections being rounded and merging with said diagonal section in the direction of the liquid supply flow, said diagonal section being provided with a' water discharge port, an annular valve seat on said diagonal section surrounding said discharge port, said tubuiar casing being provided with an air inlet port with a valve seat therearound, the lower transverse section being shaped to conform to the contour of the annular water discharge port 7 valve seat and diverging downward in the direction of the liquid supply flow, and a valve member hingedly supported from said upper transverse section and swingable between said water discharge port valve seat and said air inlet valve seat.

11. A vacuum breaker for a liquid supply system, comprising a tubular casing having means for checking backflow of the liquid supply and for breaking a vacuum occurring therein, supporting means for said tubular casing including inlet and outlet threaded fittings arranged on opposite ends of said tubular casing for-connecting said tubular casing to a supply and a discharge pipe, said outlet fitting having an inner tapered shoulder cooperating with the lower end of said tubular casing to provide a tight press fit therebetween, said inlet fitting having an inner abutting ledge engaging said tubular casing together with packing means on said abutting ledge providing a tight seal between said inlet fitting and said tubular casing, an outer tubular shell enclosing said tubular casing, and means for connecting the opposite ends of said tubular shell to said inlet and outlet fittings so that said fittings are held in spaced relationship and a space is provided between said tubular casing and said tubular shell.

12. A vacuum breaker for a liquid supply system, comprising a tubular casing having means for checking back-flow of the liquid supply and for breaking a vacuum occurring therein, supporting means for said tubular casing including inlet and outlet threaded fittings arranged on opposite ends of said tubular casing for connecting said tubular casing to asupply and a discharge pipe, said outlet fitting having an inner tapered shoulder cooperating with the lower end of said tubular casing to provide a fluid tight press fit therebetween, said inlet fitting having an inner abutting ledge engaging said tubular casing together with packing means on said abutting ledge providing a fluid tight seal ber tween said inlet fitting and said tubular member, an outer tubular shell enclosing said tubular casing, means for connecting the opposite ends of said tubular shell to said inlet and outlet fittings so that said fittings are held in spaced relationship and a space is provided between said tubular casing and said tubular shell, said tubular shell having an air passage therein providing access of the atmosphere to the tubular casing,

and a hood on said inlet fitting overhanging said air passage to shield the same.

13. A vacuum breaker for a liquid supply system, comprising a vertically disposed tubular casing, a partition arranged within said tubular casing, said partition comprising a diagonal portion provided with a water discharge opening, a valve seat therefor and a transverse portion serving to support the partition within said tubular casing, said tubular casing being provided with an air inlet opening, a valve seat therefor, disposed adjacent said check valve seat, a valve member arranged for movement alternately into engagement with either of said valve seats, and means for supporting said valve member from the transverse portion of said partition, said valve member support means comprising a pivot, a bracket having leg portions passing through the transverse portion and engaging said pivot, and a lug on the transverse portion" for securing said bracket in position thereon.

14. A valve member arranged for pivotal movement into closing engagement with either of two oppositely disposed valve seats, a projecting lip portion defining the peripheral edge portion of said valvemember and arranged to overlap one of said seats when in engagement therewith, said projecting lip portion comprising rigid side sections and a flexible lower section, and flexible annular inner portions arranged on opposite sides of said valve member for closure upon the associated valve seats.

WILLIAM E. SLOAN. IRVING H. RUSSELL. 

